Fixing device

ABSTRACT

The invention relates to a fixing device with a lug strip ( 10 ), at least one end ( 12 ) of said lug strip ( 10 ) being bent to form a fixing loop ( 14 ), comprising a fixing space by means of two enclosing pieces ( 16 ) into which a retaining means ( 22, 24 ) may be introduced, whereby said retaining means ( 22, 24 ) comprise two opposing fixing pieces ( 26 ) for a unit with the both enclosing pieces ( 16 ) and is provided with a functional piece ( 28, 30 ). The both fixing pieces ( 26 ), diametrically opposed to each other on the respective retaining means ( 22, 24 ), comprise fixing surfaces. The functional piece ( 28, 30 ) runs at least partly perpendicular to the common longitudinal axis of the fixing piece ( 26 ) and each fixing surface is provided with a convex curvature. A fixing device with few components, which can be easily finished to give a lug at the site of assembly without any additions is achieved, whereby the convex curvature of the functional piece ( 28, 30 ) runs perpendicular to the common longitudinal axis of the fixing pieces ( 26 ) essentially along a semi-circle and the separate end surfaces of the fixing pieces ( 26 ) are provided with an insertion ramp on the side thereof facing away from the functional piece ( 28, 30 ) which each run into the corresponding semi-circle.

[0001] The invention relates to a fixing device with a lug strip, at least one end of the lug strip being bent to form a mounting loop which by means of two enclosing elements encloses a mounting space into which retaining means may be inserted and which has at least one mounting opening positioned between the two enclosing elements, the retaining means having two diametrically opposite retaining elements for contact with the two enclosing elements and possessing an operating element which projects from the mounting opening in the mounting space when the retaining means is installed, it being possible to introduce at least one of the two retaining elements of the retaining means into the installation space in one direction of installation by way of the mounting opening, it being possible to move the retaining elements into contact from below with the enclosing elements after pivoting of the at least partly introduced retaining means in a fastening direction extending transversely to the direction of introduction, the dimensions of the mounting space being such that the two retaining elements of the retaining means introduced are inserted into the mounting space with a predetermined amount of clearance, the respective retaining means having two diametrically opposite retaining elements with retaining surfaces, the operating element extending at least in part perpendicularly to the common longitudinal axis of the retaining elements, and the respective retaining surface being provided with a convex curvature.

[0002] A fastening device disclosed in EP-A-0 508 050 has a flexible one-piece lug strip, the two free ends being sealable by a sealing element for fixing a tubular component in position. For the purpose of forming the sealing element in question the two free ends of the lug strip are bent and each forms a mounting loop each with two enclosing elements which delimit between themselves a mounting space which communicates with the exterior by way of a mounting opening. Cylindrical retaining means are introduced into the two mounting spaces, the enclosing elements of one mounting loop rigidly enclosing bolt-like retaining means, while the other mounting loop with its two enclosing elements loosely encompasses a pivot element as retaining means. An internal hexagonal screw the functional length of which may be adjusted and fixed in this position by means of a lock nut extends through the pivot element. The internal hexagonal screw also ensures that the pivot element cannot unintentionally fall sideways out of the mounting space of the associated mounting loop. The bolt-like retaining means, secured by the opposite mounting loop, has a recess which extends upward to communicate with the exterior and which is provided with a lug-like catch element, so that, after the internal hexagonal screw has been introduced from above, this screw may be fastened by its head component in the catch for a tightening process. The sealing element as thus configured may be detachably locked quickly for securing tubular bodies inside the lug strip and the screw introduced into the catch is suitably fastened by tightening.

[0003] The disclosed clamp is generally preinstalled at the factory and fastened locally to the element to be secured. Predetermined lugs may accordingly be employed for one fastening purpose only as a function of the diameter of the tubular element to be secured. As regards the retaining means premounted in the mounting loop so as to be stationary, the disclosed fastening device can hardly be supplemented locally and disassembly of the lug likewise is possible only as part of an entire process and involves all operating elements. Because of the large number of operating elements and their assembly at the place of production the disclosed solution is also relatively cost-intensive, so that it is too expensive from the technical viewpoint to apply for simple fastening purposes.

[0004] Generic DE-B-1 256 013 discloses a strip clamp for connecting two ends of a pipeline or a hose with a socket piece, this strip clamp consisting of a tightening strap and a tightening device mounted near the end of the tightening strap, the ends of the tightening strap projecting above the fastening points of the tightening device for strip clamps being provided with tightening devices removable by conventional means after loosening, on one side with a slot and on the other with a hook extending perpendicularly outward and engaged in the slot during tightening so as to effect locking.

[0005] In the case of the disclosed solution the two tightening straps facing each other are appropriately bent in their enclosing elements and thus form mounting openings and mounting spaces, both for a fastening bolt with external threading for tightening and in the form of fastening element with a tightening nut provided with internal threading.

[0006] Both the fastening bolt and the fastening element are configured as differently shaped retaining means each of which is guided in the lug strip so as to be pivotable by way of two diametrically opposite retaining elements mounted in the associated mounting spaces. The respective retaining element is configured as a bolt or pin with retaining surfaces circular in cross-section the convex curvature of which follows the course of the curvature of the bent lug strip in the area of the associated mounting space. The fastening element in question with lock nut, on the other hand, is to be mounted in the lug strip on-site at the manufacturing firm and the fastening bolt with the external threading for tightening as an operating element may be introduced locally, that is, at the site of installation of the clamp, into the associated mounting space by way of the mounting opening designed for this purpose. Although the slot-like mounting opening in the lug strip is relatively wide, interlocking of the associated retaining means often occurs during the process of introduction; this correspondingly complicates the process of introduction and mounting. Should the disclosed clamp design be modified for other application purposes within the range of its operating elements, such modification can be accomplished only with difficulty because of the selected connections between lug strip and operating element.

[0007] On the basis of this state of the art the object of the invention is, in contrast, to create a fastening device with a small number of components, one which may be added directly to a clamp as a supplement and which can perform a wide range of fastening tasks, a device characterized by ease of assembly and safety in operation. The object as thus formulated is attained with a fastening device having the features specified in claim 1 in its entirety.

[0008] In that, as specified in the preamble of claim 1, the convex curvature facing the operating element extends more or less along a semicircular arc transversely to the common longitudinal axis of the retaining elements and in that each of the end surfaces of the retaining elements spaced some distance from each other is provided with an insertion bevel which undergoes transition to the associated semicircular arc, it is possible first to prepare the lug strip and make it available for assembly and then, locally, by introduction of the respective retaining means into the associated mounting loop, to prepare the fastening means required for fastening the clamp directly on other structural components. By appropriate bending of the lug strip the latter may be adapted simply on-site to the geometric external dimensions of the element to be fastened, which element is not necessarily tubular.

[0009] Introduction of the retaining means into the respective mounting loop is made easier by the semicircular shape of the retaining elements and their insertion bevels, in that the fastening process not only is immediately clear to an assembler but also the respective assembly and if necessary disassembly process is so easy that the necessary steps may be taken in rapid sequence for a plurality of lug connections without the possibility of occurrence of disruptive interlocking or the like. In the aggregate this results in distinctly improved handling of the fastening device and any faulty assembly is also eliminated in this way. In addition, the lug strip may be loosened immediately after removal of the retaining means, while the retaining means may also remain at the fastening site. However, it is also possible, of course, to introduce the fastening device as a whole, as assembled, immediately at the factory. The fastening device claimed for the invention has proved to be suitable in particular for use in the motor vehicle industry, for example, when it is necessary securely to fasten air filters subject to vibration or the like within a vehicle.

[0010] In one preferred embodiment of the fastening device claimed for the invention the mounting opening of the respective mounting loop extends along the longitudinal axis of the lug strip, the mounting opening having at least two component areas with different opening cross-sections and the component area with the larger opening cross-section being used for introduction of the restraining means and the other component area with the smaller opening cross-section for passage of the operating element when the retaining means has been fully introduced into the mounting loop. As a result, simplicity of introduction of the respective retaining means into the associated mounting loop is ensured, while with the retaining means introduced, if the operating element passes through the component area with the smaller cross-section, cannot unintentionally fall from the mounting loop, something which definitely facilitates assembly and handling of the fastening device claimed for the invention.

[0011] In another preferred embodiment of the fastening device claimed for the invention, in addition to the two component areas a third component area is present, one which is in the form of a slot with further reduced opening cross-section and adjoins the second component area and forms a stop for the operating element. Forces acting on the mounting loop, such as ones in the form of vibration forces, can be reliably diverted to the lug strip. Although the clamp structure is naturally weakened by the slot, a higher level of stability is thereby reached. In that the slot additionally forms a stop for the operating element, subsequent automatic assumption by the lug strip, after its installation, of the proper associated operating position relative to the operating element of the respective retaining means is ensured.

[0012] Preferably additional provision is made such that the respective retaining means has two diametrically opposite retaining means with retaining surfaces and such that the operating element extends perpendicularly to the common longitudinal axis of the retaining elements.

[0013] Preferably provision is also made such that the enclosing elements of the respective mounting loop are provided with a convex curvature to form contact surfaces which correspond to the convex curvature of the retaining surfaces when the retaining means have been fixed in position. Adaptation of the convex curvature of contact surfaces to retaining surfaces ensures reliable contact, along with the desired diversion of forces into the lug strip, when the retaining means has been fixed in position.

[0014] In another preferred embodiment of the fastening device claimed for the invention the respective operating element is provided on its free end with a screw insertion threading or has a lock bolt whose free ends end in the area of the two longitudinal edges of the lug strip after the retaining means have been introduced. As a result, the operating element with the lock bolt may be fastened, by simple manipulation by way of a type of clip and the respective retaining means, by a lock nut provided for the screw insertion and the lug strip may be suitably tightened for a fastening process.

[0015] Preferably the retaining means is designed to be of one piece in the form of a hammer head, the lug strip being susceptible to manual bending. The retaining means preferably consists of a form of steel for screws and accordingly is tough enough to absorb strong forces. In that the lug strip is highly flexible although it is made of a steel strip, it may be immediately adapted to local fastening process conditions.

[0016] The fastening device claimed for the invention is described in detail in what follows with reference to an exemplary embodiment. In the drawing, in the form of diagrams not drawn to scale,

[0017]FIG. 1 presents a top view of the fastening device, with lug strip and retaining means introduced;

[0018]FIG. 2 a side view of the fastening device shown in FIG. 1;

[0019]FIGS. 3, 4, and 5 two different side views and a bottom view of one form of retaining means;

[0020]FIGS. 6, 7, and 8 two different side views and a bottom view of the other form of retaining means.

[0021] As is to be seen in FIGS. 1 and 2, the fastening device has a one-piece flexible lug strip 10. The length and width of the lug strip 10 may be predetermined. The two free ends 12 of the lug strip are bent and so each of them forms a mounting loop 14. Each mounting loop 14 is bounded laterally by two enclosing elements 16 which enclose a mounting space 18 and between them delimit a mounting opening 20 which connects the mounting space 18 to the exterior.

[0022] Retaining means 22, 24 may be introduced into the two mounting spaces 18, the respective retaining means 22, 24 having two diametrically opposite retaining elements 26 for contact with the two enclosing elements 16 as well as an operating element 28, 30 which projects into the respective associated mounting space 18 from the mounting opening 20 after the retaining means 22, 24 have been introduced.

[0023] The respective retaining means 22, 24 may be introduced with one of its two retaining elements 26 into the associated mounting space 18 by way of the mounting opening 20 in one direction of insertion, the direction of insertion in question extending in parallel with the longitudinal axis 32 of the lug strip 10, so that, when the respective retaining means 22, 24 is inserted, the longitudinal axis of its respective two retaining elements 26 is oriented more or less in parallel with the longitudinal axis 32 referred to of the lug strip 10. If one retaining element 26 of the respective retaining means 22,24 is introduced into the mounting space 18 by way of the mounting opening 20, it is pivoted manually in one direction of fastening, which extends more or less transversely to the direction of insertion and accordingly perpendicularly to the longitudinal axis 32 of the lug strip 10, by pivoting of the retaining means 22, 24.

[0024] In the respective installation situation the two retaining elements 26 of the respective retaining means 22, 24 then establish contact from below by their lower end with the respective enclosing element 16 of a mounting loop 14. The fastening situation in question of the two retaining means 22, 24 corresponds to that illustrated in FIGS. 1 and 2. It is also to be noted that, at least in this installation situation, the retaining means 22, 24 may be pivoted about their respective longitudinal axis 34 as it is guided while moving in the mounting space 18, as viewed in the line of sight toward FIGS. 1 and 2, clockwise for the left retaining means 24 and counterclockwise for the opposite retaining means 22, and accordingly both retaining means 22, 24 are mounted in the assigned mounting loop 14 in the direction of their insertion so that they may be pivoted back and consequently extracted from mounting loop 14 as the lug strip 10 is released.

[0025] The mounting opening 20 of the respective mounting loop 14 thus extends along the longitudinal axis 32 of the lug strip 10, the mounting opening 20 having three component areas 36, 38, and 40 with different opening cross-sections, and in particular ones decreasing in size in this sequence. As has already been pointed out, the first component area 36 has the largest opening cross-section for insertion of the respective retaining means 22, 24, while the following second component area 38 with smaller opening cross-section allows passage of the operating element 28, 30 after the retaining means 22, 24 has been fully introduced into the mounting loop 14.

[0026] The third component area 40 adjoining the second component area 40 is in the form of a type of slot opening and so a stop is formed for the respective operating element 28,30 at the point of transition of the openings with different cross-sections between the second and third component areas 38 and 40, the stop ensuring a preassembly location, something which makes mounting of the fastening device on other components, such as ones in the interior of a vehicle, much easier.

[0027] As is to be seen in FIGS. 3 to 8, the respective fastening means 22, 24 has two diametrically opposite fastening elements 26 with retaining surfaces 42, the longitudinal axis 44 of the operating element 28, 30 extending perpendicularly to the common longitudinal axis 34 of the retaining elements 26. As is also to be seen in the diagrams, the respective retaining surface 42 is provided with a convex curvature, each of the end surfaces separated by some distance from each other of the retaining elements 26 being provided on the side facing away from the operating element 28,30 with an insertion bevel 46. The insertion bevel 46 in particular forms an angle of about 45° with the lower side 48, which extends perpendicularly to the longitudinal axis 44 of the operating elements 28, 30. In addition, as is to be seen in FIGS. 4 and 7, the convexly curved retaining surfaces 42 as seen more or less from the side, that is, transversely to their common longitudinal axis 34, form a semicircular arc 43 which faces in the direction of the respective operating element 28, 30. Provision may also be made such that the retaining surfaces 42 of the retaining elements 26 are provided at least to some extent with chamfers 58; this arrangement also facilitates the processes of introduction and removal for the respective retaining element 26.

[0028] The enclosing elements 16 of the respective mounting loop 14 are also provided with a convex curvature to form contact surfaces 50 (see FIG. 2), this convex curvature corresponding to that of the retaining surfaces 42 referred to when the retaining means 22, 24 have been fixed in position. The respective retaining means 22, 24 may accordingly follow the curvature of the contact surfaces 50 by way of their retaining surfaces 42, so that coincident contact with the enclosing elements 16 is achieved, with the result that, in the fastened area of the respective retaining means in particular, covering bottom contact with the enclosing elements is achieved, with the result that high forces may be dissipated into the lug strip 10 when the lug strip 10 is in the fastened state.

[0029] The operating element 28 shown in FIGS. 3 to 5 is provided on its free end with a screw insertion threading 52 so that the retaining means 22 may be secured to mounting parts not shown here by way of a lock nut assembly. When the retaining means 24 is configured as shown in FIGS. 6 to 8, the operating element 30 is provided on its free end with a fastening bolt 54 whose free ends as shown in FIG. 1 end in the area of the two longitudinal edges 56 of the lug strip 10. The fastening bolt 54 in question may be fastened to mounting parts by two clasp-like fingers of another fastening element (not shown), it being possible to pivot the lug strip 10 to a limited extent, at least as far as the stop referred to opposite the retaining surfaces 42 of the retaining means 22. If the lug strip 10 then overlaps an element (not shown), such as one in the form of a tubular disk filter or the like, the lug strip 10 may be placed under tension by way of the retaining means 22 with its screw insertion threading 52 correspondingly on a fastening element by way of the lock nut connection to ensure firm seating.

[0030] The fastening device illustrated consists of a small number of components, specifically the lug strip 10 and the two retaining means 22, 24, so that the assembly may be supplemented at the production factory, but by preference locally at the installation site. The assembly in question is easy to disassemble, so that when the element to be fastened, such as one in the form of a disk filter or the like, is replaced, the replacement process may be completed rapidly. The respective replacement and installation periods may accordingly also be kept brief. 

1. A fixing device with a lug strip (10), at least one end (12) of the lug strip (10) being bent to form a mounting loop (14) which by means of two enclosing elements (16) encloses a mounting space (18) into which a retaining means (22, 24) may be introduced and which has at least one mounting opening (20) positioned between the two enclosing elements (16), the retaining means (22, 24) having two opposite retaining elements (26) for contact with the two enclosing elements (16) and having an operating element (28, 30) which, when the retaining means (22, 24) have been introduced into the mounting space (18), projects from the mounting opening (20), it being possible to introduce the retaining means (22, 24) with at least one of its two retaining elements (26) into the mounting space (18) by way of the mounting opening (20), it being possible for the retaining elements (26) to be brought into contact from below with the enclosing elements (16) after pivoting of the at least partly introduced retaining means (22, 24) in one direction of fastening extending transversely to the direction of introduction of the retaining elements (26), the mounting space (18) being dimensioned so that the retaining means (22, 24) introduced, with its two retaining elements (26), fits into the mounting space (18) with a predetermined clearance, the respective retaining means (22, 24) having two retaining elements (26), with retaining surfaces (42), positioned diametrically opposite each other, the operating element (28, 30) extending at least in part perpendicularly to the common longitudinal axis (34) of the retaining elements (26), and the respective retaining surface (42) being provided with a convex curvature, characterized in that the convex curvature facing the operating element (28, 30) extends more or less along a semicircular arc (43) transversely to the common longitudinal axis (34) of the retaining elements (26) and in that the two end surfaces of the retaining elements (26) positioned a certain distance from each other on the side facing away from the operating element (28, 30) are each provided with an insertion bevel (46) which effects transition to the associated semicircular arc (43).
 2. The fastening device as claimed in claim 1, wherein the mounting opening (20) of the respective mounting loop (14) extends along the longitudinal axis (32) of the lug strip (10), wherein the mounting opening (20) has at least two component areas (36, 38) with different opening cross-sections, and wherein the component area with the larger opening cross-section serves the purpose of introduction of the retaining means (22, 24) and the other component area (38) with the smaller opening cross-section serves the purpose of passage of the operating element (28, 30) when the retaining means (28, 30) [sic.] has been fully introduced into the mounting loop (14).
 3. The fastening device as claimed in claim 2, wherein, in addition to the two component areas (36, 38) there is present a third component area (40) configured as a slot with additionally reduced opening cross-section adjoining the second component area (38) in the direction of the lug strip (10) and forming a stop for the operating element (28, 30).
 4. The fastening device as claimed in one of claims 1 to 3, wherein the enclosing elements (16) of the respective mounting loop (14) are provided, for the purpose of forming contact surfaces (50), with a convex curvature which corresponds to the convex curvature of the retaining surfaces (42) when the retaining means (22, 24) has been fastened.
 5. The fastening device as claimed in one of claims 1 to 4, wherein the respective operating element (28, 30) is provided on its free end with a screw insertion threading (52) or a fastening bolt (54) the free ends of which end in the area of the two longitudinal edges (56) of the lug strip (10) after the retaining means (24) has been introduced.
 6. The fastening device as claimed in one of claims 1 to 5, wherein the retaining means (22, 24) is designed as one piece in the form of a hammer head and wherein the lug strip (10) is designed so that it may be bent manually.
 7. The fastening device as claimed in one of claims 1 to 6, wherein the insertion bevels (46) when rounded undergo transition to a level bottom surface (47), which faces away from the operating element (28, 30), of the retaining means (22, 24).
 8. The fastening device as claimed in one of claims 1 to 7, wherein the retaining surfaces (42) of the retaining elements (26) are provided at least in part on the edge side with chamfers (58). 